1. Field of Invention
This invention relates to a stage device and to a method of manufacturing a stage device. This invention also relates to a position controlling method, and to an exposure device and a method of manufacturing an exposure device. This invention also relates to a device made by the exposure device and to a method of manufacturing such a device. More specifically, this invention relates to a stage device that controls a position and posture of an object with a high degree of accuracy, and to a method of manufacturing the stage device. The invention also relates to a method of controlling a position of an object using the stage device. The invention further relates to an exposure device having the stage device, and to a method of manufacturing the exposure device. The invention further relates to a device, such as a micro-device, that is manufactured by the exposure device, and to a method of manufacturing the device.
2. Description of Related Art
Conventionally, in a lithographic process to manufacture a semiconductor element, a liquid crystal display element, or the like, an exposure device has been used that transfers a pattern formed on a mask or a reticle (hereafter referred to as "reticle") onto a substrate such as a glass plate or a wafer, where a resist or the like is coated, through a projection optical system.
In this type of exposure device, in order to position a wafer (or other substrate) at an exposure position with high accuracy, a stage device has been used to control a position and a posture in six degrees-of-freedom, such as X, Y, Z, .theta..sub.X, .theta..sub.Y, .theta..sub.Z, of a wafer holder that holds the wafer. On this type of stage device, conventionally, two X-axis driving linear motors, two Y-axis driving linear motors, and a stage driving guide are provided. These elements drive an X-Y stage in the two-dimensional X-Y direction, a .theta..sub.Z table loaded on this X-Y stage, and a three degrees-of-freedom leveling table, mounted on the .theta..sub.Z table, that drives a wafer holder that holds a wafer in three degrees-of-freedom such as Z, .theta..sub.X, and .theta..sub.Y (focusing and leveling). This stage device has a large number of moving parts, and a high thrust motor is needed as a linear motor in order to obtain the required speed. Furthermore, because the dimensions of the moving parts are large, the range of motion is also restricted.
Recently, a stage device with a flat motor has been developed where positioning of a wafer table on which a wafer is loaded can be performed in three degrees-of-freedom directions such as X, Y, and .theta..sub.Z in a non-contact state. This enables a wafer to be positioned at high speed and with high accuracy without the effects of a mechanical guide surface. Additionally, a long life expectancy can be expected by avoiding mechanical friction. With respect to this stage device, a variable magnetic reluctance driving method has been suggested that combines two linear pulse motors of a variable magnetic reluctance driving method, such as Sawyer motors. Additionally, a stage device has been suggested that uses a flat motor as a driving device using a Lorentz electromagnetic driving method. These are disclosed in, for example, Japanese Patent Laid-Open Publication No. 58-175020 and U.S. Pat. No. 5,196,745. Furthermore, it has been suggested that the position and posture control of the wafer in the six degrees-of-freedom directions can be performed by using a stage on which a wafer is loaded that is driven in three degrees-of-freedom directions such as X, Y, .theta..sub.Z by a flat motor, and at the same time using a leveling table that can control a position and a posture of the substrate loaded on the stage in the remaining three degrees-of-freedom directions.
Incidentally, as a device rule (practical minimum line width) becomes refined along with the high density of semiconductor elements, high resolution is increasingly requested as a performance capability of an exposure device. Because of this, the exposure wavelength has shortened. As an exposure device for the next generation and thereafter, it may be desirable to use vacuum ultraviolet (VUV) light with a wavelength of 200 nm or less, X-rays in which the wavelength is even shorter, and charged particle beams, such as an electron beam, as an exposure energy beam. In this type of exposure device, when oxygen exists in the path of the energy beam, energy beam absorbing substances such as haze and ozone (O.sub.3) occur due to photochemical reactions, or an energy beam is directly absorbed by air particles. Therefore, it is necessary to replace air with nitrogen N.sub.2, helium He, or the like, or use a vacuum environment.
However, in the stage device using the above-mentioned flat motor, because of the characteristics of the device, the stage device cannot be used in a non-air environment because the stage is floated and supported in a non-contact state by using an air bearing or the like.
Additionally, a large wafer has been recently developed, and a stage device with a large driving force has been expected in order to move the wafer.